Electrically heated and controlled steam boiler



Apr. 17, 1923. 1,451,847

w. H. ROWE ELECTRIGALLY HEATED AND CONTROLLED STEAM BOILER Filed Feb. 10 1922 A15- i fo ney.

Patented Apr. 17, 1923.

UNITED STATES WILLIAM H. ROWE. orJAoKsoNvILLE, FLORIDA.

' nLEc'rnIoALLY mnrrnn am) CONTROLLED STEAK BOILER.

Application filed February 10, 1922. Serial 1K0. 535,442.

To all whom ifmay concern:

Be it known that I, WILnIAM H. ROWE, a citizen of the United. States, residing at Jacksonville, county of Duval, and State of Florida, have invented certain new and useful Improvements in Electrically Heated and Controlled Steam Boilers, of which the following is .a specification. a

My invention relates to electrically heated and controlled steam boilers of the smaller types. The main and particular objects and advantages of my invention are; to provide a steam boiler in which "thesteam can be generated in the shortest possible time; which will be economical to operate; and which will," at all times, be under perfect. automaticcontrol as to pressure and water content. p

A further object is to'construct and connect the heat-elements in such a manner that they may be easily removed and replaced, without necessitating the emptying of the boiler. Another object-is to provide a boiler, safe ,and convenient to operate, simple in construction, easy to repair and keep in order, and comparatively inexpensive to manufacture;

Theseand various other objects and advantages will be clearly understood from the followingdescription and the accompanying drawing, in which:

Fig. 1 is a front elevation of a preferred embodiment of my invention. This view is shown partly in cross-section.

Fig. 2 is a cross-sectional elevation of one of the heat elements.

Fig. 3 is a somewhat distorted diagram, showing the electric wiring in Fig. 1.

While I have shown. a vertical boiler, it

will be understood that my invention lends itself as readily to a horizontal boiler. It will alsobe seen that modification might be made without departing from the scope of my invention.

In a general way the invention maybe described as consisting of a number of electric heat elements inserted in metal tubes, the tubes welded or otherwise fastened to the .bottom of a steam boiler and extending a certain distance into the boiler. cylinder connected, at its lower end, by a pipe to the upper or steam part of the boiler, a PlStOIl. and piston rod operating in the cylinder, and a lever connected between the piston rod and an electric controller, thereby actuating the controller, causing it to disconnect tube.

or connect a certain number of the heat elements, as the pressure in the boiler increases or decreases.

Another cylinder ,is connected, at its upper and lower ends, by means of pipes to the boilers these pipes being located, respectively, above and below the water level in .the boiler. A float operates in this cylinder and actuates, by means of a rod, a switch whereby, the feed water pump is started or stopped, as the water level falls or rises in the boiler.

Referring to the vagious views, simultaneously, lvis the boiler 'shell,'2 the bottom plate, and 3 the dome of a vertical, steam boiler. A plurality of circular holes are drilled or punched in .the bottom plate 2, and in these holes tubes 4 are welded or otherwise fastened; the tubes are closed at their upper ends 5, as shown ofi Fig. 2, and

extend a certain distance up into the boiler, but not above the water level. Externally threaded flanges 6 are welded to the lower ends of-the tubes 4, these flanges also being welded to the bottom plate 2, thus forming water tight joints. I The heat elements, which are inserted in the tubes 1, each consists of, a cylindrical insulator 7 having flanges or shoulders 8 and 9. The flange 8 fits in the tube 4, while the flange 9 is slightly larger fitting inside the threaded flange 6, but prevented, by. reason of its enlarged diameter, from entering the An internally threaded cap 10 is screwed on the flangeG and clamps the insulator inplace. The cap 10 has a circular opening through which a shoulder 11, formed on flange 9, projects. p

A rod 12, threaded at both ends, passes through a hole in the insulator 7. This rod is provided with a single nut 13 at its upper end and two nuts 14 and 15 at its lower end. A heating'wire 16 is closely wound around the insulator, one end of this wire passes through a hole in flange 8 and is fastened under the nut 18, while the other end passes .wires 20", 21 22 and 23 to the contact points '20, 23;, 22, and 23 in the controller box 24. The controller box also contains.

to the returifi'nain 26. v

A cylinder 27 is Connected, by means of pipes and pipe fittings 28, to the steam space of the boiler. A piston 29 operates in the cylindera'nd is connected, by means of piston rod 30, to a lever 31, having an elongated slot 32, in which a pin 33, fastened in the piston rod, engages. The other end of the lever 31 is attached to the shaft 34, to which the contact segment 25 is also attached. A spring 35 balances the pressure in the cylinder, and a threaded bushing 36 allows for adjusting the tension of the spring. Holes 37 are provided in the upper the contact segment 25, which is connected part of the cylinder, to enable the steam to escape, should the piston rise to the top of the cylinder, thus acting as a safety valve.

Another cylinder 38 is connected at its lower end. by means of pipes and pipe fittings 39, to the water space of the boiler, and at its lower end, by means of pipes and fittings 40, to the steam space of the boiler. A float 41, having a rod 42, is free to rise and fall in the cylinder and is actuated by the water in the boiler. rod 42 is connected with an arm43, mounted on a switch panel 44. This arm engages with a contact 45, also mounted on the panel 44; wires 46 and 47 lead .to a motor operating a feed pump and the main wire. 48'

shows a steam gauge, 49 the steam outlet, 50 the water inlet, and 51 the water level in the boiler.

The upper end of the The operation of the boiler isas follows: The current having been turned on, the

water in the boiler is heated by the heat ele-' ing, first with contact 23, then contact 22, then contact 21 and finally with contact 20. In thus disconnecting the contacts, the groups of heat elements are gradually cut out of service and the pressure regulated.

i As the water level in the boiled descends, the float 41, in the cylinder 38, also descends until the arm 43 engages with the contact 45, whereupon the motor circuit is closed and the feed pumpstarted. As the water level again ascends the arm is disengaged and the feed pump stopped.

Having described my invention and its operation, what I claim as new and wish to protect by Letters Patent is:

In an electrically heated boiler; a plurality of electric heating elements inserted in tubes, secured to the underside of the boiler and projecting into it; a cylinder communi-' eating by means, of a pipe with the steam space in the boiler; a piston and a piston .rod free to move in said cylinder; a lever connecting said piston rod with an electricqqntroller; and the heating elements connected by wires to said controller.

In testimony whereof, I, WILLIAM H. ROWE, have signed my name to this specification in the presence of two subscribing witnesses, this 27th day of January,l922.

WILLIAM H; ROWE.

Witnesses:

CHAS. A. GREEN, CHAS. H. HAwirINs. 

